1. Field of the Invention
The present invention relates to a wireless call system for checking visitors applicable to, for example, housing.
2. Description of the Related Art
An example of a conventional wireless call system is disclosed in Japanese Unexamined Patent Publication No. 11-239224. This system includes an indoor unit for checking a visitor. With the system, a resident in a house can check a visitor, unlock a door, and invite the visitor into the house without compromising security.
Conventional wireless call systems of the type mentioned above employ fixed indoor units. Whenever a visitor comes to operate an outdoor unit of the system, a resident in the house for which the system is installed must go to the indoor unit in the house to check the visitor. The resident may be a bedridden person or a person who is in bed with a cold. In this case, it is hard for the resident to go to the indoor unit every time a visitor comes, and if no answer is returned to the visitor from inside the house and if the door is locked, the visitor will leave without result. In this way, the conventional wireless call systems are unable to allow bedridden persons or persons in bed with sick to properly answer visitors.